Furnace wall



Aug. 12, 1930. J. c. HOBBS 1,772,486

' FURNAQE WALL Fil ed June 1925 2 Sheets-Sheet 1 INVENTOR 7M 0. 6% BY %4Q /afl A TTORNEYS AAAAAAAAAA LL INVENTOR I v C? 466% ATTORNEYS PatentedAug. 12, .1930

PATENT oFnc James 0. 3033s, or ramasvnm; onro FURNACE WALLApplicationflled June 17, 1925. Serial No. 37,638.

My invention more particularly relates to a furnace wall provided withmeans for increasing the rate of heat transmission through the wall fromthe furnace side, and

thereby increasing the life of the wall or permitting'higher furnacetemperatures and resulting economy or both.

Other features of my invention will be apparent from the specificationand will be particularly pointed out in the claims.

My invention will best be understood by reference to the accompanyingdrawings, in which I have illustrated one embodiment thereof and inwhich Fig. 1 is a vertical section through a furnace embodyin my invention and illustrating a portion 0 the boiler located above the same;Fig. 2 is a fragmentary sectional view illustrating a portion of v Fig.1 and taken along the line 2-2 of Fig.- '3, looking in the direction ofthe arrows, and Fig. 3 is a section taken along the line 3'-3 of Fig. 2looking in the direction of the arrows.

Like reference characters indicate like parts throughout the drawings.

Referring to the drawings, 10 and 11 are the'front and rear walls,respectively, of a furnace, the inside face of one of the side wallsbeing indicated at 12. The furnace is fired by any suitable fuel, in theembodiment illustrated by powdered fuel, the burner for which isindicated at 13." In the form shown, the nozzle 13 extends through anopening 14, in a suitable roof or arch 15 located at the upper frontportion of the furnace, having an upwardly extendingpob tion 16. Anauxiliary wall 17 issupported upon and extends upwardly from the rearwall 11, a suitable'boiler being located above the furnace, a portion ofthe tubes of which boiler are indicated at 18, and which are connectedat their ends to a downtake header 19 and an uptake header 20.

In the form shown, aheat insulating cas- 45 ing 21 is spaced from thefront wall 10. The rear wall of the furnace, in the embodimentillustrated, comprises two spaced sections 11 and 11", which arepreferably connected together by bonding tiles 11.

"In accordance with my invention, members of good heat conductingmaterial, as compared with the refractory members with which the wall isformed, are placed in the inner section 11 of the wall and extendoutwardly therefrom. In the form shown, these members 22 consist of ametallic plate or plates, formed of a good heat conducting material,such as copper, which are laid between the tiles 111 of the section 11of the wall, and are preferably spaced at their inner ends somewhat fromthe inner face of the wall, as at 23, in order to protect the ends ofthe members from the heat of the furnac'e. The space 23 between the endsof the members 22 and the inner face of the wall 35 is filled in withsuitable clay or cement.

The outer ends 22 of the members 22 extend into the space between thetwo sections lla'nd 11,but preferably extend short of the section 11'?to permit of the free circulation of air around the ends of the plates.The outer ends of the members 22 which are located next to the bondingtiles 11 are prefe'rably bent away from the same, as at 22",

in" order to permit of the circulation of air 5 around the ends of thosemembers.-

Preferably, the side walls are made in substantially the same manner asthe rear wall; that is to say, the side walls are formed with spacedsections which are connected by the bonding tiles 11, as indicated indotted lines, thus forming a plurality of ducts between the sections.The members 22 also preferably extend around the sides of the furnace,as also indicated in dotted lines. The front wall is also preferablyprovided with bond-ing tiles and cooling plates as illustrated. I

Preferably,air is introduced into the space between the sections 11? and11 of therear wall, and in the form illustrated, a blower 24 is used forforcing a blast of airinto the said spaces. The blower leads to aconduit or manifold 25,-to which are connected branch pipes or ducts 26,leading to the respective spaces between the sections '11 and 11" of therear wall, which are located between the successive bonding tiles 11.The air flows through the spaces between the sections of the rear walland between the sections of the side walls, the same flowin over the r eouter M ends 22 and 22" of the members'22, and absorbing heat therefrom,and flows around to the front of the furnace into the space 27, betweenthe front wall 10 and the casing 21 and through suitable openings 28,into the front of the furnace where it is mixed with the powdered fuelentering the furnace from the nozzle 13.

The members 22 being formed of a materialwhich is a much betterconductor of heat than are the refractory members of which the wall isprincipally formed, conduct the heat from the furnace side of the wallinto the space between the sections 11 and 11 where the air impingesagainst the outer ends 22* and 22 of the members and absorb the heattherefrom, the heat so absorbed being utilized to raise the temperatureof the entering air. At the same time, by carrying the heat away fromthe inner face of the wall or walls, they are maintained at asufficiently low temperature greatly to increase the life of the spacedapart, both sections being made of material of low heat conductivity,members of .good heat conducting material as compared to the material ofsaid sections placed in the inside section with their inner edges spacedfrom the inside face of said sectlon and their other edges extendinginto the space between the sections.

2. In a furnace, a wall made in sections spaced apart with bonding tileextending across the space and constituting a portion of each wallsection, both sections being made of material of lowgheat conductivity,members of good heat conducting material as compared to the material ofsaid sections placed in the inside section with their inner edges spacedfrom the inside face of said section and their other edges extendinginto the space between the sections.

3. In a furnace, a wall made in sections spaced apart, both sectionsbeing madeof material of low heat conductivity, thin metal plates in theinner section extending into the space between the sections, and meansprotecting the inner edges of said plates from the heat of the furnace.

4. In a furnace, a wall" made in sections spaced apart, b'eth sectionsbeing made of material of-low'heat conductivity, and thin metal platesinthe inner section extending into the space between the sections,saidsections being connected at intervals by bonding tile-extendingacross'said space and constituting a part of each section.

spaced apart, both sections being made of material of low heatconductivity, and thin metal plates in theinner section extending intothe space between the sections, said sec; tions being connected atintervals by bonding tile extending across said space and constituting aart of each section, some metal plates being bent away from said tile insaid space.

6. In a'furnace, a wall made in sections spaced apart, both sectionsbeing made of material oflow heat conductivity, tile extending betweensaid sections to divide the space between said sections into a pluralityof ducts, members of good heat conducting material as compared to thematerial of said sections placed in the inside section with their inneredges spaced from the inside face ofof said section and their otheredges extending into the ducts between the sections.

8. In a furnace, a wall made in sections spaced apart, both sectionsbeing made of material of low heat conductivity, metal plates disposedin the inner section and extending into the space between the sections,and means protecting the inner edges of sa1d plates from the heat of thefurnace.

9. In a furnace, a wall of refractory material, both sections being madeof refractory material, said wall being made in sections spaced apart,tile extending between said sections to divide the space between sa1dsections into a plurality of ducts, and members of good heat conductingmaterial as compared to the refractory material placed in the insidesection with their outer edges extending into the ducts between thesections.

10. In a furnace, a wall of refractory material made in two sectionsspaced apart, both sections being made of material of low heatconductivity, a plurality of ducts formed in the space between saidsections, means for causing passage of air through sa1d ducts, andmembers of relatively good heat conducting material disposed in saidinner sections and extending into said ducts.

11. In a furnace, a wall of-refractory material made in two sectionsspaced apart, both sections being made of material of low heatconductivity, a plurality of ducts formed in the space between saidsections, means for causing passage of air through said ducts, andmembers of relatively good heat conducting material disposed in saidinner sections and extending into said ducts, and means protectin theinner edges of said members from the eat of thefurnace. 1

12. In a furnace, a wall made in two sec 5 tions spaced apart, bothsections being formed of refractory blocks, horizontally disposed metalplates between said blocks and extend ing into the space between saidsections, and means protecting. the inner. edges of said 10 plates fromthe heat of the furnace.

JAMES C. HOBBS.

